Causes of Sudden Shutdown of Diesel Generator Set during Operation

1. Automatic shutdown when fuel is exhausted, usually displayed as a low speed shutdown.

2. Failsafe shutdown. Protection shutdown due to external fault signal input. For example, the most basic protection systems for common generator sets include overload, high water temperature, low oil pressure, overspeed, etc.

3. High water temperature shutdown: when the diesel generator set detects that the water temperature is higher than the set value, the diesel generator set will shut down immediately. In case of high water temperature, it is necessary to find out the cause of the fault before restarting the machine.

4. Low oil pressure shutdown: when the diesel generator set detects that the oil pressure is lower than the set value, the diesel generator set will shut down immediately. After shutdown, check the oil level again and find out the cause of the fault before restarting the diesel generator set.

5. In addition to the above fault shutdown, a series of protective shutdowns, such as overvoltage, low-voltage, overfrequency, low-frequency, high battery voltage, and low battery voltage, are available based on different needs and control methods.

6. Check whether the alarm shuts down, a, low oil pressure b, high water temperature c, overspeed, etc.

7. Check whether there is overload and whether the inlet and outlet pipes are smooth.

8. Check whether relevant parts are broken or loose, and check whether the oil tank is short of oil.

9. Check the fuel injection pump for damage.

10. Check the speed sensor, electronic speed regulator, actuator, etc.

11. Mechanical speed regulation of diesel engine

Diesel engine speed regulation is divided into electronic speed regulation and mechanical speed regulation. If it is a mechanical speed regulation, there is an oil pump mechanism on the diesel engine that controls the oil quantity and oil path, which seems to be called a common rail oil pump (please forget the specific name). There is a pull rod on it that controls the oil quantity, and for the time being, it is called a speed regulating pull rod. On both sides of the speed regulating pull rod, there are a speed limiting (high-speed) push rod and a speed regulating push rod. After starting and running for 20s, the low pressure is reported, I don't know if the voltage and frequency can't go up all the time. If they can't go up all the time, it may be caused by the speed not going up. You can adjust the speed control lever and try it. Any diesel unit failure usually has a major fault, and once the major fault is resolved, the resulting series of minor faults will be resolved.

12. Loose voltage sampling line

This is easy to understand. If the voltage sampling line is loose, the voltage cannot be measured.

13. Remanence magnetism

If the generator has no residual magnetism, the voltage system of the generator cannot be established at the beginning. For this problem, we need to know how much V the excitation output of the AVR regulator of the generator is, and then connect the corresponding voltage source to the excitation output line for magnetization (the voltage type should be corresponding, and the polarity should not be reversed).

14. Ground fault

If the outgoing line is three-phase grounded, the voltage and current are very low. At this time, it is mainly necessary to check whether the grounding discharge device (such as the grounding switch) is closed or grounded.

15. Regulator plate fault

Due to changes in environmental factors, the parameters of the AVR regulator are no longer applicable and need to be readjusted. Generally speaking, this problem does not occur in non parallel diesel units because the parameters of the regulator are fixed (400V), which is generally not adjustable. This problem can only occur in parallel units, because the AVR regulator is adjusted based on the voltage of the main bus during parallel operation, and it is not immutable, At this time, the parallel device generally has a voltage regulating signal sent to the AVR regulator. In this case, either check whether the voltage regulating signal is connected incorrectly, or try quickly using electronic controls (parallel device, regulator, etc.) to readjust the voltage during startup.

16. The varistor or rectifier bridge diode on the generator winding is damaged

The role of the varistor is: when an overvoltage fault occurs, the varistor is turned on to reduce voltage. If the varistor is broken down or turned on for other reasons, it can be imagined that the voltage must be very low. The rectifier bridge has six diodes, and the set DC power supply is used to supply devices such as the regulator and excitation. If the rectifier bridge diode is damaged, the role of the regulator and excitation devices will be greatly reduced.

Jiangsu Meao Power Technology Co., Ltd. is an important manufacturer of diesel generators. The company mainly manufactures and sells diesel generator sets with power of 3-3000kW, mobile power station of 24-600kW, Marine emergency diesel generator set of 24-800kW, gas generator set, heavy oil generator set and all kinds of imported series, special series (trailer, static speaker, mobile lighthouse, container, etc.) diesel generator At the same time, we are engaged in generator set maintenance and after-sale service of generator set accessories.